Here is an interesting article about two ActiveSync bugs that are currently occurring in connection with Apple iOS:
The article is very interesting, as it goes deep into error analysis. In my view, it is very worth reading.
I can understand both problems and am also waiting for an update, although I don't care who delivers the update, I just want it to work again...
Specifically, the issue is that appointment invitations are forwarded to participants without the user doing anything. The iOS feature "With current travel time" is probably responsible for this problem. This iOS feature can be switched off as a workaround:
Settings -> Calendar -> Standard notes -> Deactivate "With current travel time".
For the second problem there is unfortunately no workaround for the iOS Mail app, here the read/unread flag is not synchronized in the mailbox. This problem also sometimes occurs for me. As an alternative, you can still use Outlook for iOS, where these problems do not occur in my experience.
The Clueless Guy is also right in his conclusion: It is not the only flag that is affected, I have also noticed problems with another flag: When a mail is forwarded from an iOS device, the mailbox does not show that the mail was forwarded (date / time). The text "You forwarded this message on XX" is missing:
However, it does not always occur, I have observed the problem more frequently in the French mobile network (Orange Telecom). The next Exchange CU should be released soon, let's see if it gets better then. However, I suspect that Apple will have to deliver a corresponding update.